Bug #114878 "missing table" in MySQL NDB cluster
Submitted: 4 May 9:39 Modified: 7 May 12:06
Reporter: CunDi Fang Email Updates:
Status: Can't repeat Impact on me:
None 
Category:MySQL Cluster: Cluster (NDB) storage engine Severity:S2 (Serious)
Version:8.0.35-cluster MySQL Cluster Community S OS:Any
Assigned to: MySQL Verification Team CPU Architecture:Any

[4 May 9:39] CunDi Fang
Description:
Hello, I found a bug in 8.0.35-cluster version of MYSQL cluster. This can result in us not being able to see tables on a node where they should be.

Failure to reproduce success is demanding on injection time.

The detail is as follow. We need at least four nodes.

I am executing the following alter table statement on a node:

NODE 1 Poc 1:
```
Please see the file I have uploaded which contains the sql statement involved along with the time of execution of that sql statement and the final result.
```

NODE 2 Poc 2:
```
Please see the file I have uploaded which contains the sql statement involved along with the time of execution of that sql statement and the final result.
```

NODE 3 Poc 3:
```
Please see the file I have uploaded which contains the sql statement involved along with the time of execution of that sql statement and the final result.
```

NODE 4 Poc 4:
```
Please see the file I have uploaded which contains the sql statement involved along with the time of execution of that sql statement and the final result.
```

It doesn't make sense that this error message should not appear, because we are not deleting the table, but in the view of this node, the table "disappears".

How to repeat:
Importing the database file I give later, and then executing Poc. Note that this bug is very demanding on the execution time of the statement.

Architecture Information:
'''
[NDBD DEFAULT]
NoOfReplicas =2
DataMemory = 512M
IndexMemory = 64M

[NDB_MGMD]
NodeId=1
hostname =192.172.10.8
datadir =/var/lib/mysql-cluster

[NDBD]
NodeId =2
hostname =192.172.10.9
datadir =/usr/local/mysql-cluster/data
NodeGroup=0
[NDBD]
NodeId =3
hostname =192.172.10.10
datadir =/usr/local/mysql-cluster/data
NodeGroup=1
[NDBD]
NodeId =4
hostname =192.172.10.11
datadir =/usr/local/mysql-cluster/data
NodeGroup=0
[NDBD]
NodeId =5
hostname =192.172.10.12
datadir =/usr/local/mysql-cluster/data
NodeGroup=1

[mysqld]
NodeId =6
hostname =192.172.10.9
[mysqld]
NodeId =7
hostname =192.172.10.10
[mysqld]
NodeId =8
hostname =192.172.10.11
[mysqld]
NodeId =9
hostname =192.172.10.12
'''

Suggested fix:
There should be a problem at some point in the execution of the alter statement that causes the table to be invisible on other nodes, causing the execution of the statement on that node to fail.
[7 May 12:06] CunDi Fang
Well, I will continue to try to reproduce this issue in my environment and will commit again if I hear back.